AC impedance & phasors worksheet with answers

Free printable AC impedance & phasors worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
12 V50 HzR = 10 ΩL = 250 mH

A series RL circuit is connected to a 12 V (rms), 50 Hz supply. Find the magnitude of the impedance |Z|.

V = 12 V (rms)f = 50 HzR = 10 ΩL = 250 mH
|Z| = Ω
2.Easy
12 V50 HzR = 80 ΩL = 20 mHI

A series RL circuit is connected to a 12 V (rms), 50 Hz supply. Find the rms current I.

V = 12 V (rms)f = 50 HzR = 80 ΩL = 20 mH
I = A
3.Medium
50 V200 HzR = 100 ΩL = 100 mHC = 22 µFI

A series RLC circuit is connected to a 50 V (rms), 200 Hz supply. Find the real power P taken from the supply.

V = 50 V (rms)f = 200 HzR = 100 ΩL = 100 mHC = 22 µF
P = W
4.Medium
120 V500 HzR = 60 ΩC = 2.2 µFI

A resistor and a capacitor are connected in parallel across a 120 V (rms), 500 Hz supply. Find the rms current I.

V = 120 V (rms)f = 500 HzR = 60 ΩC = 2.2 µF
I = A
5.Hard
120 V500 HzR = 60 ΩL = 150 mHC = 100 µF

A series RLC circuit is connected to a 120 V (rms), 500 Hz supply. Find the resonant frequency f0 of the circuit.

V = 120 V (rms)f = 500 HzR = 60 ΩL = 150 mHC = 100 µF
f0 = Hz
6.Hard
24 Vf0​R = 2 ΩL = 5 mHC = 0.47 µF

A series RLC circuit is driven by a 24 V (rms) source whose frequency is set to the resonant frequency of the circuit. Find the rms voltage VL across the inductor.

V = 24 V (rms)R = 2 ΩL = 5 mHC = 0.47 µF
VL = V

Answer key

  1. 1. |Z| = 79.17 Ω
  2. 2. I = 0.1495 A
  3. 3. P = 13.88 W
  4. 4. I = 2.165 A
  5. 5. f0 = 41.09 Hz
  6. 6. VL = 1238 V

Full step-by-step solutions: practise this topic on examproblems.com.